Component Tests and General Diagnostics

INSPECTION

1. Turn the ignition switch to ON.
2. Turn the defogger switch to ON.




3. Wrap the tips of tester pins with aluminum foil to avoid damage to heat wire.




4. Measure the voltage at wire center with DC voltmeter.

NOTE:
- If the measured value is 12 volts, heat wire is open between wire center and positive (+) end.
- If zero volt, heat wire is open between wire center and ground.

5. Apply positive lead of voltmeter to positive terminal of heat wire, and then move the negative lead along the wire up to negative terminal end. If voltage changes from zero to several volts during movement of lead, heat wire is open at the voltage change point.